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Chemical Engineering :: Fluid Mechanics

  1. In turbulent flow, a rough pipe has the same friction factor as a smooth pipe

  2. A.

     In the zone of complete turbulence

    B.

     When the roughness projections are much smaller than the thickness of the laminar film

    C.

     Everywhere in the transition zone

    D.

     When the friction factor is independent of the Reynold's number


  3. In centrifugal pump operation, the cavitation can be eliminated by maintaining suction pressure __________ the vapor pressure of the liquid at the suction temperature.

  4. A.

     Lower than

    B.

     Higher than

    C.

     Equal to

    D.

     None of these


  5. Drag co-efficient for motion of spherical particles in a stationary fluid in the stoke's law range is

  6. A.

     24/NRe,p

    B.

     16/NRe,p

    C.

     64/NRe,p

    D.

     48/NRe,p


  7. Vena-contracta formed during flow of a liquid through an orificemeter has

  8. A.

     Minimum liquid cross-section

    B.

     More diameter compared to orifice diameter

    C.

     Minimum velocity of fluid stream

    D.

     None of these


  9. Hydraulic intensifier is used for increasing the

  10. A.

     Rate of velocity of liquid supply

    B.

     Rate of flow through delivery pipeline of a pump

    C.

     Intensity of pressure of the liquid

    D.

     Momentum rate through delivery pipe


  11. In case of end to end connection of two or more pipes in series, the __________ each pipe.

  12. A.

     Same rate of flow passes through

    B.

     Head loss is same through

    C.

     Rate of flow in each pipe is proportional to the length of

    D.

     Total flow rate is the sum of flow rate in


  13. For the manometer set up shown in the figure, the pressure difference PA - PB is given by

  14. A.

     (ρH - ρair)gH

    B.

     (ρH - ρL)gH

    C.

     (ρH - ρL) gH + (ρL - ρair) . g(L - H)

    D.

     (ρH - ρL) gL + (ρL - ρair)gH


  15. Pressure difference between two points in vessels, pipelines or in two different pipelines can be measured by a differential manometer. The pressure difference measured as the mm of water coloumn in case of mercury-water, differential manometer is equal to (where, H = difference in height of mercury column in mm).

  16. A.

     H

    B.

     12.6 H

    C.

     13.6 H

    D.

     14.6 H


  17. The time of oscillation of a floating body is

  18. A.

     Longer, if metacentric height is increased

    B.

     Independent of the metacentric height

    C.

     Dependent on the buoyant forces only

    D.

     None of these


  19. The line traced by a single fluid particle as it moves over a period of time is called __________ line.

  20. A.

     Stream

    B.

     Path

    C.

     Equipotential

    D.

     None of these